RNA interference as a key to knockdown overexpressed cyclooxygenase-2 gene in tumour cells

Silencing those genes that are overexpressed in cancer and contribute to the survival and progression of tumour cells is the aim of several researches. Cyclooxygenase-2 (COX-2) is one of the most intensively studied genes since it is overexpressed in most tumours, mainly in colon cancer. The use of specific COX-2 inhibitors to treat colon cancer has generated great enthusiasm. Yet, the side effects of some inhibitors emerging during long-term treatment have caused much concern. Genes silencing by RNA interference (RNAi) has led to new directions in the field of experimental oncology. In this study, we detected sequences directed against COX-2 mRNA, that potently downregulate COX-2 gene expression and inhibit phorbol 12-myristate 13-acetate-induced angiogenesis in vitro in a specific, nontoxic manner. Moreover, we found that the insertion of a specific cassette carrying anti-COX-2 short hairpin RNA sequence into a viral vector (pSUPER.retro) greatly increased silencing potency in a colon cancer cell line (HT29) without activating any interferon response. Phenotypically, COX-2 deficient HT29 cells showed a significant impairment of their in vitro malignant behaviour. Thus, the retroviral approach enhancing COX-2 knockdown, mediated by RNAi, proved to be an useful tool to better understand the role of COX-2 in colon cancer. Furthermore, the higher infection efficiency we observed in tumour cells, if compared to normal endothelial cells, may disclose the possibility to specifically treat tumour cells without impairing endothelial COX-2 activity

Non-protein coding RNA biomarkers and differential expression in cancers: a review

<p>Abstract</p> <p>Background</p> <p>In these years a huge number of human transcripts has been found that do not code for proteins, named non-protein coding RNAs. In most cases, small (miRNAs, snoRNAs) and long RNAs (antisense RNA, dsRNA, and long RNA species) have many roles, functioning as regulators of other mRNAs, at transcriptional and post-transcriptional level, and controlling protein ubiquitination and degradation. Various species of npcRNAs have been found differentially expressed in different types of cancer. This review discusses the published data and new results on the expression of a subset of npcRNAs.</p> <p>Conclusion</p> <p>These results underscore the complexity of the RNA world and provide further evidence on the involvement of functional RNAs in cancer cell growth control.</p

Assimilation of Business Intelligence Systems: The Mediating Role of Organizational Knowledge Culture

This study examined the assimilation of business intelligence (BI) systems in firms. Based on the innovation assimilation concepts from information systems (IS) studies and considering the resource-based theory (RBT) as the theoretical underpinning, an initial research model was developed. The model was then validated with survey data that we collected from 153 managers and executives from Malaysia. The collected data were analyzed by partialleast-squares (PLS) methods. The results show that the assimilation stages (i.e., implementation and routinization) are not sequential (in other words, successful implementation does not ensure routinized use of BI systems); rather, implementation of BI systems enhances organizational knowledge culture, which in turn drives routinized use of BI systems. Data analyses also find that implementation of BI systems is dependent on three factors: quality of the BI system itself, quality of its users, and the governance of BI systems in firms. Our results offer new insights to theory and practice

MicroRNAs: Small RNAs with a big role in gene regulation

MicroRNAs are a family of small, non-coding RNAs that regulate gene expression in a sequence-specific manner. The two founding members of the microRNA family were originally identified in Caenorhabditis elegans as genes that were required for the timed regulation of developmental events. Since then, hundreds of microRNAs have been identified in almost all metazoan genomes, including worms, flies, plants and mammals. MicroRNAs have diverse expression patterns and might regulate various developmental and physiological processes. Their discovery adds a new dimension to our understanding of complex gene regulatory networks